Why is Solar Cycle 24 Starting So Slowly?

In summary, the sun has had a slow start to its new activity cycle. There have been multiple sunspot groups, but they are all members of the new Solar Cycle 24. There is still a long way to go before the cycle peaks, but the numbers are a sign that the sun is starting to wake up.
  • #1
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The fingerprint of the new solar cycle
The new solar activity cycle still puzzles all solar physicists due to its very slow start. The sunpot index for November 2009 is still only 4.2, well below many predictions (SIDC predictions: SM=6, CM=13). Although, the number of spotless days decreased strongly compared to the last two years, with multiple but small sunspot groups.
. . . .
http://sidc.oma.be/news/119/welcome.html

A Long Filament Erupts (December 14, 2009)
http://soho.nascom.nasa.gov/pickoftheweek/old/11dec2009/


Solar Cycle 24 is off to a slow start.

http://www.spaceweather.com/images2...lank.gif?PHPSESSID=e4cknd2c58dnbuja23ubqbih15

http://www.spaceweather.com/images2009/15dec09/1035_anim2.gif?PHPSESSID=e4cknd2c58dnbuja23ubqbih15
 
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  • #2
So far, 65% of the days in December have brought sunspots--a sharp increase in percentages compared to earlier months of 2009 when sunspots were surpassingly rare. All six of December's sunspot groups have been members of new Solar Cycle 24. These numbers could herald the sun's awakening from the deepest solar minimum in nearly a century and a livelier sun in 2010.
Ref: http://www.spaceweather.com/archive.php?view=1&day=27&month=12&year=2009


Large Sunspot Group (December 18, 2009)
http://soho.nascom.nasa.gov/pickoftheweek/old/18dec2009/

For the first time in over a very quiet solar year, the Sun as seen by SOHO is sporting 5 active regions (Dec. 22, 2009). The brightest regions in the extreme UV image are magnetic active regions. And the brighter an area appears, then we know that its magnetic energy is stronger. Two of these regions are associated with dark sunspots when viewed in visible wavelengths; the other areas have not developed into sunspots yet. This activity could signal that the long solar minimum is beginning to give way to greater activity levels, but we will just have to wait and see.
Awakening Sun (December 25, 2009)
http://soho.nascom.nasa.gov/pickoftheweek/old/25dec2009/
 
  • #3
May 27, 2010

Solar Scientists Agree That the Sun's Recent Behavior Is Odd, but the Explanation Remains Elusive
The most recent solar minimum was both long and pronounced. But why?

MIAMI—In very rough terms, the sun's activity ebbs and flows in an 11-year cycle, with flares, coronal mass ejections and other energetic phenomena peaking at what is called solar maximum and bottoming out at solar minimum. Sunspots, markers of magnetic activity on the sun's surface, provide a visual proxy to mark the cycle's evolution, appearing in droves at maximum and all but disappearing at minimum. But the behavior of our host star is not as predictable as all that—the most recent solar minimum was surprisingly deep and long, finally bottoming out around late 2008 or so.

Solar physicists here at the semiannual meeting of the American Astronomical Society this week offered a number of mechanisms to shed light on what has been happening on the sun of late, but conceded that the final answer—or more likely answers—remains opaque. . . . .
 
  • #4
I've been watching this solar cycle almost daily on spaceweather.com and to me personally its seems pretty normal. Sure it was off to a delayed start but still within the bounds of long-cycle variations. I'm one of those with the opinion that you can't really predict the sun anyway. Our observation of it is way to short-lived for that. Anyhow, March and April was quite active in terms of sunspots if I recall correctly, plus many filaments that produced flares. The past few weeks have been a tad too quiet though...IMO.
 
  • #5


I am intrigued by the slow start of Solar Cycle 24 and the unexpected behavior of the sunspot index. The current sunspot numbers are well below many predictions, indicating that the sun is not behaving as we thought it would at this point in the cycle. This could have significant implications for our understanding of solar activity and its effects on Earth's climate and technology.

One possible explanation for this slow start could be the influence of the Sun's magnetic field. The sunspot index is closely related to the strength and complexity of the Sun's magnetic field, and it is possible that there are changes in the field that we are not yet fully aware of. This could be due to the Sun's internal processes, or even interactions with other celestial bodies.

Another factor that could be contributing to the slow start is the overall decrease in sunspot activity in recent years. The number of spotless days, where there are no visible sunspots on the Sun's surface, has been increasing. This could indicate a larger trend of decreased solar activity, which could have significant implications for Earth's climate and space weather.

The recent eruption of a long filament on the Sun's surface is also an interesting event to consider in relation to the slow start of Solar Cycle 24. Filaments are long, dark structures made of cooler plasma that are suspended above the Sun's surface by magnetic fields. When these filaments erupt, they can release large amounts of energy and material into space. This eruption could be a sign of increased solar activity, but it is important to continue monitoring the Sun to see if this is a one-time event or part of a larger trend.

Overall, the slow start of Solar Cycle 24 is a reminder that the Sun is a complex and dynamic system that we are still working to fully understand. As scientists, we must continue to gather data and analyze it to gain a better understanding of the Sun's behavior and its effects on our planet. Only then can we make accurate predictions and prepare for any potential impacts on Earth and our technology.
 

1. What is the "Slow Start to Solar Cycle 24"?

The solar cycle refers to the periodic change in the Sun's activity, marked by changes in the number of sunspots and solar flares. Solar Cycle 24 is the current cycle, which began in 2008. The "slow start" refers to the fact that this cycle has had a lower number of sunspots and overall lower solar activity compared to previous cycles.

2. How long is a typical solar cycle?

A typical solar cycle lasts about 11 years, with some variation. However, the exact length and intensity of each cycle can vary, making it difficult to predict the exact duration and strength of the next cycle.

3. What causes the slow start to Solar Cycle 24?

The exact cause of the slow start to Solar Cycle 24 is still being studied and debated by scientists. Some theories suggest that changes in the Sun's magnetic field and variations in solar wind may be responsible. Others suggest that it is a natural part of the cycle's fluctuations and is not necessarily abnormal.

4. How does the slow start to Solar Cycle 24 affect Earth?

The Sun's activity can have various effects on Earth, including changes in the Earth's magnetic field and the frequency and intensity of solar storms. The slow start to Solar Cycle 24 may result in fewer solar storms and a decrease in the number of auroras visible in certain parts of the world. However, scientists are still studying the potential impacts of this cycle on Earth.

5. Will the next solar cycle be affected by the slow start of Solar Cycle 24?

It is difficult to predict the exact effects of the slow start to Solar Cycle 24 on the next cycle. Some scientists believe that the next cycle may be weaker as a result, while others suggest that it may have no significant impact. Further research and observation are needed to fully understand the potential effects on the next solar cycle.

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